1. Field of the Invention
The invention relates to an induction system for an internal combustion engine and more particularly to an induction system for the powering internal combustion engine of a snowmobile.
2. Description of the Related Art
It is the normal practice to position a powering internal combustion engine of a snowmobile within an engine compartment. This is done at least in part to protect the engine from the surrounding environment. Air is generally drawn from the engine compartment into the induction system of the engine.
When the snowmobile is operated, the temperature of the air drawn from inside the engine compartment is generally warmer than that of the outside air because of the heat generated by the engine. If the temperature of the induction air is too high, engine performance is compromised.
It is, therefore, a principal object of the present invention to provide an induction system for the internal combustion engine of a snowmobile wherein induction air is normally supplied to the induction system from outside of the engine compartment.
However, because the induction air is drawn from the outside rather than from the protected confines of the engine compartment, in certain operating conditions it may be more likely that snow and other foreign materials will enter the induction system along with the induction air, thereby degrading engine performance or harming the engine. Thus, in certain limited conditions, such as when the snowmobile is operated in deep snow, it may be more desirable to induct air from inside the engine compartment.
It is therefore a further object of the present invention to provide an induction system for the internal combustion engine of a snowmobile wherein the induction air can selectively be drawn from either outside or inside of the engine compartment.